Determining the electronic structure of La3Ni2O7 is an essential step towards uncovering their superconducting mechanism. It is widely believed that the bilayer apical oxygens play an important role in the bilayer La3Ni2O7 electronic structure. Applying the hybrid exchange-correlation functionals, we obtain a more accurate electronic structure of La3Ni2O7 at its high-pressure phase, where the binding dz2 band is below the Fermi level owing to apical oxygen. The symmetry properties of this electronic structure and its corresponding tight-binding model are further analyzed. We find the antisymmetric part is highly entangled leading to a minimal nearly degenerate two-orbital model. Then, the apical oxygen vacancies effect is studied using the dynamical cluster approximation. This disorder effect strongly destroys the antisymmetric β Fermi surface leading to the possible disappearance of superconductivity.
@article{arxiv.2412.20465,
title = {The electronic structure and disorder effect of La$_3$Ni$_2$O$_{7}$ superconductor},
author = {Yuxin Wang and Yi Zhang and Kun Jiang},
journal= {arXiv preprint arXiv:2412.20465},
year = {2025}
}